\pgfkeys{/tikz/.cd,%
	start coordinate/.initial= { 0,\vertfactor },%
	start coordinate/.initial= { 0,\vertfactor },%
	start coordinate/.initial= { 0,\vertfactor },%
	start coordinate/.initial= { 0,\vertfactor },%
	another/. style= { 0,\vertfactor } ,%
	start coordinate/.initial={0,\vertfactor}{something else},
}
